Heat transferrer



O. H. HARTMANN ET AL HEAT TRANSFERRER Sept. 15, 1931.

Filed Feb. 24, 1930 2 Sheets-Sheet l lhvenfora 0%Eflaort'rnann anwjizzffmng,

Sept. 15 1931. 0. H. HARTMANN ET AL 1,823,800

HEAT TRANSFERREH Filed Feb. 24, 1950 2 Sheets-Sheet 2 Patented Sept. l15, 1931 UNITED STATES PATENT OFFICEVY OTTO H. HARTMANN AND MAX HANNIG,OF CASSEL-WIIiHELMSHOHE, GERMANYQAS- SIGNORS TO SCHMIDTSCHEHEISSDAMPF-GESELLSCHAFT MIT BESCHRANKTER HAF- TUNG, OFCASSEL-WILHELMSHOHE, GERMANY, A CORPORATION OF GERMANY HEAT TRANSFERRERApplication filed February 24, 1930, Serial No. 430,944, and in GermanyApril 25, 1929.

The invention relates to heat transferrers 1n WhlCh the heating elementsare arranged mside a drum or other container with connections to theoutside thereof, the heatingv elements running lengthwise of the drum orthe like and consisting of groups of tubes which at their free ends areprovided with headers for the necessary connections.

In heat-transferring apparatus of this kind as specially designed forthe indirect generation of high-pressure steam, difiiculties occur inpreventing the stresses rising to too high a degree in consequence ofthe inability of the parts concerned to expand freely.

According to the present invention, such difficulties are overcome byconnecting the lower headers rigidly with the outlet fittings, while theupper headers are connected .Wl'z'h the inlet fittings by relativelylong tubes provided with one or more bends.

With such a construction, upon expansion of the heatingelements, theupper headers can move in the longitudinal direction in relation to. thelower headers so that stresses "5 of too high a degree due to largevariations in temperature are avoided.

Referring to the accompanying diagram matic drawings, which showdifi'erent forms of the'invention by way of example Figure 1 shows avertical longitudinal section through a drum and its contents with thecentre part broken away;

' Figure 2 shows a corresponding horizontal section, and Figure 3 across-section of the drum with the heating elements in end view;

' Figure 4 is a vertical longitudinal section through the drum of amodified form of the invention showing one of the central heatingelements,

Figure 5 being a similar view showing one I of the outerheating'elements, while Figure 6 shows a cross section. Finally, Figures7 and 8 show respectively a vertical longitudinal and cross section of amodified form of the invention shown in Figures 4 to 6.

In all the drawings heat transferrer is indicated by the numeral, 1, thecontainer in the example shown consisting of a thick-walled drum for theindirect generation of high-pressure steam, access to the interior ofthe drum for the insertion of the longitudinally-disposed heatingelements being obtained at both ends through the manhole openings, 2.

These heating elements co'nsistof groups I of U-tubes which at theirfree ends are con'-' nected to corresponding headers, 4 and 5. The lowerheaders, 4, are connected inside the drum by short lengths of straighttube, 6, tothe outlet fittings, 7 ,while the connection of the upperheaders, 5, with the corresponding fittings, 8, is effected byrelatively long S-tubes, 9, attached above the Us to the upper headers,5, which are offset longitudinally as shown in relation to the lowerheaders, 4, in order to provide for the necessary length of S-tube, 9.The lower headers, 4, arein this way in rigid association with the drum,1,-while the upperheaders, owing to the long connecting. tubes, 9, aremovable in relation to the drum, so that the parts concerned cannot beoverstressed when differential changes of temperature occuril theheating elements. 1

In the example shown, the U-tube's of the heating elements lie inparallel planes with their corresponding ends disposed alternately inopposite directions so thatfittings, 7 and 8, are disposed at both endsof the drum.

Through the fittings, 7, condensate is withdrawn whilethrough thefittings, 8, the heating steal n, whether it be in thesaturated orsuperheated condition, e nters and after giving up its heat ofevaporation only or its superheat in addition, flows away as condensatethrough the connections, 7

' In the form of the invention shown in Figures 4 to 6, each upperheader, 5, is offset the-container for the I longitudinally to a lessextent than in Figure 1 while the S-shaped tube, 9,'connected to itsupper part runs the whole length of the upper legs ofthe U. In thisform, the fittings, 7, for-the withdrawal of condensate all lie at oneend of the drum and the fittings, 1

In Figures 7 and 8, a further form of the invention is shown in whichfor each header, the single connecting-tube, 9, of large diameter issub-divided into a group of tubes, 10,

of small diameter to provide for the necessary expansion.

This arrangement is applicable to both forms of the invention describedabove.

.In any of the forms of the invention described, the Us may be replacedby straight lengths of tube connected to a return header.

Although the invention is intended rimarily for the indirect generationof highpressure steam, it is also applicable to steam-- heatedsuperheaters, evaporators or othei 35 steam-heated heat transferrers.

We claim 2- 1. A heat transferrer with heating elements arrangedlengthwise in a drum or other contain er, these elements consisting ofgroups of U-tubes having one set of legs at a higher elevation than theother, their upper legs be ing connected with upper headers, throughwhich steam is admitted, and their lower legs being connected withlowerheaders, through which condensate, is withdrawn, the lower headersbeingin rigid association with the drum and the upper headers being connectedto the drum by a relatively long tube having one or more bends to giveit flexibility, said tube running longitudinally of the drum through asection thereof occupied by the lower legs. i

2. -A heat transferrer as claimed in claim 1,

. in which certain of the heating elements with their connections arereversed end for end in relation to certain other of the heatingelements. I 7 H 3. A heat transferrer as claimed in claim 1,

- in which the connections for the heating steam inlet and also for thecondensate outlet of any individual heating element are disposed.

at the same end of the drum,'and the upper headers are offsetlongitudinally in relation to the lower'headers as far as is necessaryto provide sufiicient length for the curved connecting tubes.

4. A heat transferrer as claimed in claim 1, in which the connectionsfor the heatingsteam inlet and for the condensate outlet of anyindividual heating element are disposed at opposite ends of the drum,and the curved connecting tube for each of the upper headers runs nearlythe whole length of the corresponding heating element.

In testimony whereof we have afiixed our signatures.

OTTO H. HARTMANN. MAX HANNIG.

